MOTS-c peptide: FDA status, legal access, dosage and side effects
What MOTS-c is, what changed in October 2026, and how thin the human evidence is.
MOTS-c is a 16-amino-acid peptide encoded in mitochondrial DNA, studied in mice and cells for its role in cellular energy signaling. It is not FDA-approved. Since HHS’s October 30, 2026 interim policy, a licensed 503A pharmacy may compound it for subcutaneous or intramuscular injection on a patient-specific prescription. REMEVi does not currently offer MOTS-c.
MOTS-c is not FDA-approved. Since HHS’s October 2026 interim policy, a state-licensed 503A pharmacy may compound it on a patient-specific prescription under listed conditions.
REMEVi does not currently offer MOTS-c.
What changed in 2026
On October 30, 2026, HHS published an interim enforcement-discretion policy for 503A compounding (Federal Register, October 30, 2026). It says HHS does not intend to take enforcement action against a state-licensed pharmacy or federal facility that compounds one of six listed peptides, MOTS-c among them, while the 503A bulks list is developed through rulemaking.
For MOTS-c, the policy lists one route: injection, subcutaneous or intramuscular. Every condition must be met:
- A patient-specific prescription from a licensed prescriber.
- MOTS-c acetate, compounded for subcutaneous or intramuscular injection — no other route is covered.
- One active ingredient per product. A product that combines MOTS-c with another peptide or vitamin is outside the policy.
- Bulk MOTS-c from an FDA-registered facility with a valid certificate of analysis (CoA); the original manufacturer FDA-registered and CGMP-compliant.
- No device packaged with the drug other than an FDA 510(k)-cleared syringe.
- The label reads “This is a compounded drug product. Not for resale.”
- Serious adverse events are reported to FDA MedWatch.
The policy is interim and revocable. HHS says it may revisit it if a safety signal or product quality issue arises, and that it is not binding. It is not FDA approval, it does not add MOTS-c to the 503A bulks list, and it covers 503A compounding, not 503B outsourcing facilities. Comments were open for two weeks after publication (docket HHS-OASH-2026-0496).
Read the Federal Register notice · The policy explained in plain words
The other five peptides the policy lists:
How a legal MOTS-c prescription works
- A licensed prescriber evaluates you and decides whether MOTS-c is appropriate. That decision belongs to the prescriber, not to a website.
- If it is, they write a prescription for you by name, for subcutaneous or intramuscular MOTS-c.
- A state-licensed 503A pharmacy compounds it from registered, CoA-documented bulk MOTS-c, with MOTS-c as the single active ingredient.
- The product arrives labeled “This is a compounded drug product. Not for resale.”
- Any serious adverse event is reported to FDA MedWatch.
Research-grade vials vs compounded prescriptions
Vials sold online as “for research use only” are not compounded prescriptions and fall outside the HHS policy. They are not made for a named patient and nothing requires a registered source or a certificate of analysis. On August 24, 2026, FDA sent warning letters to five online peptide vendors; according to Holland & Knight, FDA found that “research use only” labels did not outweigh evidence of human use, citing the bacteriostatic water and dosing calculators sold alongside.
What research exists on MOTS-c
MOTS-c research is mostly in mice and cells. USADA notes there are no completed human clinical trials of MOTS-c. Human data are limited to measurements of the body’s own MOTS-c and an early trial of a related but different molecule. So there is little or no human outcome data for MOTS-c itself.
- Mouse and cell: Lee et al. (Cell Metabolism, 2015) described MOTS-c and gave it to mice by intraperitoneal injection, measuring insulin response and glucose handling, with skeletal muscle as the main target tissue.
- Mouse: Reynolds et al. (Nature Communications, 2021) gave MOTS-c to young, middle-aged and old mice and measured physical-performance tests.
- Human, no MOTS-c given: the same 2021 paper measured the body’s own MOTS-c in the muscle and blood of 10 young men before and after a cycling session.
- Human, a different molecule: CB4211, an analog of MOTS-c, was tested in a company-sponsored Phase 1a/1b study reported in 2021; its primary measures were safety and tolerability. Results came from a press release, not a peer-reviewed paper.
MOTS-c side effects: the short version
MOTS-c’s side effects in people are not well described: there are no completed human trials. The analog CB4211’s early trial reported injection-site reactions as its most common adverse event. Tell a licensed provider about pregnancy, breastfeeding, cancer history, allergies and every medicine you take.
MOTS-c dosage: the short version
We found no published human dose for MOTS-c by subcutaneous or intramuscular injection. Mouse studies used a different route and are not human doses. Published protocols vary; a licensed provider sets your dose; never self-dose.
MOTS-c cost: the short version
Few published prices exist for compounded MOTS-c, and those found predate the October 2026 policy. REMEVi does not currently price MOTS-c.
Has the FDA approved MOTS-c?
No. MOTS-c is not FDA-approved for any use. Since October 30, 2026, an interim HHS policy lets a state-licensed 503A pharmacy compound MOTS-c for subcutaneous or intramuscular injection on a patient-specific prescription under listed conditions. That policy is enforcement discretion, not approval, and HHS can revisit it if a safety or quality issue arises.
What does MOTS-c do?
In cells and mice, MOTS-c has been studied as a signal from mitochondria that acts on cellular energy pathways, including AMPK, mainly in skeletal muscle. What it does when injected into people has not been shown, because no completed human trial of MOTS-c has been published. It has no approved use.
Has MOTS-c been tested in humans?
Not as MOTS-c itself in a completed trial. One 2021 study measured the body’s own MOTS-c in 10 young men around exercise, without giving any. A related molecule, CB4211, was tested in a small company-sponsored early-phase trial, but it is a different compound, and its results were released by press release.
Is MOTS-c banned in sports?
Yes. According to USADA, MOTS-c is prohibited at all times, in and out of competition, under the World Anti-Doping Agency’s metabolic modulators category as an activator of AMPK. Athletes subject to testing should treat it as a banned substance whether it comes from a prescription or a research vial.
Sources
- HHS, Federal Register — Enforcement Discretion Policy Regarding 503A Compounding Using Certain Peptide Bulk Drug Substances (91 FR 68526, October 30, 2026) (read November 2, 2026)
- Holtz, Beaver & Rosen (Foley & Lardner), National Law Review, Oct 30, 2026 — HHS Announces Limited Enforcement Discretion for Compounding of Six Peptides (read November 2, 2026)
- Bigica, Nutritional Outlook, Nov 2, 2026 — What the Interim Compounding Pathway for Peptides Could Mean for Supplement Brands (read November 2, 2026)
- Holland & Knight, Oct 16, 2026 — Peptides at a Crossroads: What Wellness Providers Need to Know About HHS and FDA Actions (read November 2, 2026)
- Lee et al., Cell Metabolism 2015 — The mitochondrial-derived peptide MOTS-c promotes metabolic homeostasis and reduces obesity and insulin resistance (read November 2, 2026)
- Reynolds et al., Nature Communications 2021 — MOTS-c is an exercise-induced mitochondrial-encoded regulator of age-dependent physical decline and muscle homeostasis (read November 2, 2026)
- CohBar press release (via BioSpace), Aug 10, 2021 — Positive topline results from the Phase 1a/1b study of CB4211, an analog of MOTS-c (company-reported, not peer-reviewed) (read November 2, 2026)
- USADA — What is the MOTS-c peptide? (read November 2, 2026)
Medically reviewed by Linda West-Conforti, RN · CA RN #389453 ·